I no longer have the original edition, but the one that was reprinted in 1971. It has 322 games up to Fischer-Spassky, Los Angeles, 1966. The games themselves have a brief and glowing introduction describing how delightful the games is. For example, describing Bird-Mason, New York, 1876: For the beautiful and well sustained conduct of this game, Bird was awarded a silver cup as brilliancy prize.
Not all games have diagrams or annotations; those that do have one diagram and scanty notes. Games are by all the greats of the past: Morphy, Blackburne, Steinitz, Marshall, Anderssen, Tarrasch, Lasker, Alekhine, Capablanca, Reti, Botvinik, Tal, Petrosian, Evans, Reshevsky, Fischer and Spassky. There are also games by unknowns: Clerc, Globus, Clemens, Eisenschmidt, Finn, Nugent, Cornell, etc.
Horowitz also included in a separate section a collection of his favorite games, and then there is a brief introduction to the games broken down by period: Pre-Morphy, Morphy, Steinitz, Modern, Hypermoderns and Eclectics and finally, Russian Hegemony.
What I like about the book is that a lot of the games are not found elsewhere...many of them are long forgotten gems that are just fun to play over. Horowitz complied the games for this book over the course of several decades and examined thousands upon thousands of games and included his favorites, but even among those there were nine he enjoyed so much that he set them aside in a separate section in order to attract the reader's attention to them. So, here is one of Horowitz' favorite games from Carlsbad, 1911.
The long forgotten Carlsbad 1911 tournament was the second of four well-known international tournaments held in the spa city of Carlsbad (then the Austria-Hungary Empire). The other three tournaments were held in 1907, 1923 and 1929.
At this one twenty-six masters were invited to participate in an enormous round-robin tournament where 325 games would be played. Of the top players in the world only two were missing, Emanuel Lasker and Jose Capablanca. Richard Teichmann was the winner a point ahead of Rubinstein and Schlechter.
Richard Teichmann has often been referred to as a player who failed to achieve his potential. Vidmar wrote that Teichmann frequently finished fifth because he was comfortable in doing so, and only an “unusual stimulation” could have resulted in him playing as well as he did to win this event. Reinfeld called him phenomenally gifted master, adding that he was greatly handicapped by laziness and the loss of an eye. He was generally found in the middle of the prize list, and won so many fifth prizes that he was nicknamed Richard the Fifth. Emanuel Lasker wrote that Teichmann could easily beat the young crop of masters in a short tournament and in fact was a redoubtable opponent for anyone, but in long events the loss of his right eye always proved too severe a handicap.
Anyway, enough of Teichmann. Everybody knows of Spielmann, but few know anything about his opponent in this game, Dus-Chotimirsky. Chessdotcom has a fascinating two part article on him HERE. Of this game, Horowitz wrote: One of the marks of a great master is the ability to conjure up murderous attacks out of seemingly harmless positions. You will like the way that Spielmann commences an unexpected attack at move 22 and drives it home with sledgehammer blows. Every move tells, and Black's helplessness becomes ever more apparent.